Railway traffic controlling apparatus



Dec. 22, 1931. F. H NICHOLSON RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Feb. 2, 1931 2 Sheets-Sheet l m m w w W V a T m M 0 N @Y H a m m .& w N fiw fi k IWEm fi N N. THHIMH Q E w k N4 w k w N TN Q Q m 3% R m 3 ET wb\ MN\ mb\ F h k \H Y \N m \W a \w \w x @w $5 a @W l ci L. 3 L. mm w Al ww A vw w w m w m Dec. 22, 1931. F. H. NICHOLSON RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Feb. 2, 1931 2 Sheets-Sheet 2 INVENTOR.

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mm Q Em B M E Q RB N 5 mww Patented Dec. 22, 1931 pNiTE STATES PATENT OFFICE FRANK I-I. NICHOLSON, OF EDGEWOOD, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA 'RAILWAY TRAFFIC CONTROLLING APPARATUS Application filed February 2, 1931. Seria1;No. 512,813.

My invention relates to railway traffic'controlling apparatus, and particularly to train control apparatus of the intermittent inductive type. One feature of my invention is the provision, in apparatus of this type, of novel and improved means for giving signal indications in the cab.

I will describe one form of apparatus embodying my invention, and will then point 0 out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a diagrammatic view showing one form of trackway apparatus embodying my invention. Fig. 2 is a diagrammatic view showing one form of train carried apparatus suitable for cooperation with the trackway apparatus shown in Fig. '1 and embodying my invention.

Referring first to Fig. 1, the reference characters 1 and 1 designate the track rails of a stretch of railway track along which traffic normally moves in the direction indicated by the arrow. These rails are divided by insu: lated joints 2 to form a plurality of blocks such as 34, t5, 5-6. Each block is provid-ed with a signal designated by the reference character S with an exponent corresponding to the location, each of which is arranged to indicate proceed, caution or stop, in accordance with traffic conditions in ad Vance. The apparatus for the control of these signals forms no part of my present invention and is therefore omitted from the draw ings.

Each block is provided with apolarized track circuit comprising a source of current 38 reversibly connected across the rails by a pole-changer 39, and a track relay T selec tively responsive to the polarity of the current in the rails. Each pole-changer 39 is oper- 4o ated by the signal S for the block next in advance, and the parts are so arranged that each track relay is energized in normal di-' rection when the associated block and the block next in advance are both unoccupied, in reverse direction when the associated block 1s is a trackway loop designated by the reference character Q with an exponent corresponding to the location.

A slow-releasing repeater relay U is asso ciated with each track relay T, and is arranged to be energized when the track relay is energizedin eitherdirection and to be de energized. when thetrack' relay is deenergized. Referring to relay U, for example, the circuit for this relay is from terminal X of a suitablesource of current, through a normal anda reverse contact 10 of track relay T in multiple, and the winding of relay U to terminal Y of the same source of current. Also associated with each track relay is a code transmitter V arranged when energized to periodically open and close a contact 11. Referring to the code transmitter V when this device is at rest and relay U is energized, uninterrupted alternating current is constantly supplied to the primary of a transformer W the circuit being from terminal X, through contact 11 (then closed) of code transmitter V front contact 7 ofrelay U, primary of transformer W and front contact 8 of relay U to terminal Y. The secondary of transformer W* is connected with the loop Q}. When code transmitter V is in operation, the circuit for primary W is the tact 12 of track relay T and the winding ofcode transmitter V, to terminal Y. It follows that this code transmitter will be in operation when and only when section 34 is occupied by a train and track relay T is energized in the normal direction.

Referring now to Fig. 2, the train-carried apparatus illustrated in this view comprises a receiver C coacting'with each of the trackway inductors P, and another receiver C coacting with each of the trackway loops Q.

The receiver C is of the type commonly employed in intermittent inductive train control systems, and comprises a magnetizable core 37 provided with a primary windin 30 and a secondary winding 31. The recelver C is of the type commonly employed in continuous inductive train control systems, and comprises a magnetizable core 40 provided with two windings 4:1.

I will first describe the intermittent inductive portions of the train control apparatus, and will then explain the cooperation of this portion with the apparatus controlled by the trackway loops.

The reference character M designates a brake application magnet which is normally energized and is arranged to apply the brakes when .deenergiz'ed. This magnet is provided with a circuit which passes from terminal X .of a suitable source of current, through contact 29'of a relay R, primary 30 of receiver C and the magnet M to terminal Y of the same source of current. The winding of re lay R is provided with a circuit which passes from terminal X, through contact 29, Wind ing of relay R, secondary winding 31 to an intermediate point in the primarywinding 30, and then through theright-hand portion of this primary and magnet M to terminal Y. In accordance with usual practice in systems of this type, an asymmetric unit 32 is connectedaround primary 30 and magnet M and is poled to oppose the flow of current from the source X, Y, the purpose of this unit being to prevent damage to contacts due to sparking when the circuits for 30 and M are opened. In accordance. with usual practice,

the parts thus far described are so arranged that magnet M andrelay R are normally energized, but that when the receiver C passes over one of the trackway inductors P, relay R will be momentarily deenergized, with the result that its contacts 29 will open and will not close unless a reset circuit is closed. Contact 29 being open, both of the circuits for magnet M will be opened, and so the brakes will be applied. The reset is accomplished by means of a reset relay H which is normally deenergized, together with an acknowledging switch G having normally closed'contacts and normally open contacts. This switch G is operated by a pneumatic relay 33, which in turn is controlled by an acknowledging valve which .is-not shown in the drawings. The switch G is illustrated in its normal posit-ion. Assuming that this switch is reversed at the time that the train passes over one of the trackway inductors, an acknowledging circuit will be closed through relay H, this circuit being from terminal X, through acknowledging contact 25, winding of relay H, primary winding 30, and magnet M to terminal Y. Relay H being energized by this circuit, a reset circuit will be closed which passes from terminal X, through acknowledging contact 26, front contact 28 of relay H, winding of relay R, secondary winding 31, righthand portion of primary winding 30, and magnet M to terminal Y. After the receiver C has passed away from the inductor P, the acknowledgingswitch G may be returned to its normal position and the train may proceed without any brake application.

Referring now to the receiver C the windlugs 41 of this recelver are connected through the medium of an amplifier D with the winding of a master relay E. This relay is provided with a contact 1313 which is closed when the relay is deenergized, and a contact 1313 which is closed when the relay is energized, these contacts being alternately closed when the relay is supplied with periodically interrupted alternating current. When contact 13-13 is closed, a relay B will be energized through a circuit which will be obvious from the drawings. /Vhen contact 1313 is closed, another relay A will be energized by virtue of a circuit which will, likewise, be obvious from the drawings. -When the two contacts of relay E are alternately closed, both relays A and B will remain closed, because these relays have slowreleasing characteristics.

7 lVhen both relays A and B are energized, and the acknowledging switch G is in its normal position, an auxiliary reset circuit for relay H will be closed, this circuit being from terminal through -l'ront contact 19 of relay'B, front contact 16 of relay A, acknowledging contact 25, winding of relay H, primary winding 30 of receiver C and magnet M to terminal Y. An auxiliary reset circuit will then be closed which passes from terminal X,-through front contacts 18 and 15 of relays B and A, acknowledging contact 26, front contact 28 of relay H, winding of relay R, secondary 31, right-hand portion of primary 30, and magnet M to terminal Y. It follows that when relays A and B are both energized, manual acknowledgment of a trackway inductor P is not required.

Associated with the relays A and B are two repeater relays AP and BP. Relay AP is provided with a pick-up circuit which passes from terminal X, through the front point of contact 27 of relay H, front contact 14; of relay A, front contact 17 of relay B, and the winding of relay AP to terminal Y. It will be observed that this circuit is closed when and only when both relays A and B are energized and the reset relay H is energized.

Relay AP is provided with a stick circuit which passes from terminal X, through the back point of contact 27 of relay H, contact 24: of a pneumatic relay F, front contact of That is to say, relay B and relay AP will be to the deenergization of magnet M.

relay AP, and the winding of this relay to terminal Y. Pneumatic relay F is controlled from the brake system in such manner that contact 24 will be opened when an automatic application of the brakes has occurred due The pick-up circuit for relay BP is from terminal K, through front contact 27 of relay H, front contact 1th of relay A, back contact 17 of relay l3, and the winding of relay BP to terminal Y. Relay BP is also provided with a stick circuit which passes from terminal K, through back contact 27 of relay H, pneumatic relay Contact 2 L, front contact 22 of relay BP, and the winding of this relay to terminal Y.

The'train is provided with a cab signal having a proceed lamp 34, a caution lamp 35, and a stop lamp 36. When both of the relays A and B are energized, proceed lamp 34 will be lighted, the circuit being from terminal X, through contacts '18 and 15 of relays B and A and lamp 3A to terminal Y.

When relay BP is energized, the caution lamp 35 of the cab signal will be lighted, the circuit being from terminal X, through front contact 23 of relay BP, and the caution lamp 35 to terminal Y. hen both relays AP and BP are deenergized, the stop lamp 36 will be lighted, the circuit being from terminal X, through back contact 23 of relay Bl back contact 21 of relay AP and lamp 36 to terminal Y. The lamps 3A, 35 and 36 may be colored green, yellow, and red, respectively, or these signals may comprise lamps arranged vertically, inclined and horizontally, respectively.

The operation of the system is as follows: Assuming that the block to the right of point 6 of Fig. l is occupied by a train Z and that a following train Z equipped with the apparatus shown in Fig. 2, is proceeding through block 34, the condition of the apparatus on train Z will be as shown in Fig. 2.

energized, so that all of the lamps of the cab signal will be extinguished. hen train Z passes inductor P relay R and magnet M will become deenergized, but the train will 7' immediately encounter loop Q, and since this loop is being supplied with periodically interrupted alternating current, relays A and B on the train will both be energized, with the result that relays H and R will become energized to suppress the automatic application of the brakes. Relays A and B will both be energized as the train passes over the loop, with the result that the proceed lamp 34 of the cab signal will become lighted. After the train leaves the loop Q the ap paratus will be restored to the conditions shown in Fig. 2, so that the proceed cab signal will be extinguished. As the train passes point 5, relay E will becontinuously energized, because loop Of is being supplied with uninterrupted alternating current. Relay A will, therefore, be energized, but relay B will be deenergized. It will therefore be necessary for the engineer to acknowledge the caution indication given by signal S this will result in suppressing the automatic brake application and it will also result in energizing relay 'BP. The latter relay will remain energized as the train passes through block 5-6, so that the caution lamp'35 of the cab signal will be lighted throughout this block. As the train passes point 6, acknowledgment will againbe necessary to suppress the automatic brake application, but relay A will be'deenergized, so that both relays AP and BP will remain deenergized, with the result that the stop lamp 36 of the cab signal will become lighted and will remain lighted until the train encounters either a caution or a proceed trackway signal.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that vari ous changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what Iclaimis: I

1. In combination, a stretch of railway track divided into blocks, aninert inductor located at theentrance to each block, a trackway loop associated with each inductor, means for supplying each loop with periodically interrupted alternating current under clear conditions and with uniterrupted alternating current under caution conditions and for deenergizing the loop under stop conditions; intermittent inductive train carried brake controlling apparatus comprising the usual receiver coacting with said trackway inductors and a normally deenergized reset relay as well as an acknowledging switch; means operating when said acknowledging switch is reversed to energize said reset relay,'two train carried relays A and B, means including a receiver coacting inductively with each trackway loop for energizing both relays A and B if the loop is supplied with periodically interrupted alternating current and for energizing relay A alone if the loop is supplied with uninterrupted alternating current and for energizing relay B alone if the loop is deenergized, means operating when said acknowledging switch is in normal position and both relays A and B are energized to energize said reset relay, two cab signal relays AP and BP. means operating when said reset relay and relay A are energized to energize relay AP or relay BP ac cording as relay B is energized or deenergized,

means for subsequently keeping relay AP or relay BP energized as long as said reset relay is deenergized, means for giving a clear indication on the train when relays A and B are both energized, and means for giving a caution or a stop indication on the train according as relay BP is energized or both relays BP and AP are deenergized.

.2. In combination, a stretch of railway track divided into blocks, an inert inductor located at the entrance to each block, a trackway loop associated with each inductor, means for supplying each loop with alternating current of one character under clear conditions and of another character under caution conditions and for deenergizing the loop under stop conditions, intermittent inductive train-carried train controlling apparatus comprising the usual receiver coacting with said trackway inductors and a normally deenergized reset relay as well as an acknowledging switch, means operating when said acknowledging switch is reversed to energize said reset relay, two train-carried relays A and B, means including a receiver coacting inductively with each trackway loop for energizing both relays if the loop is supplied with current of the first characteristic and for energizing relay A alone if the loop is supplied with current of a second characteristic, means operating when said acknowledging switch is in normal position and both relays A and B are energized to energize said reset relay, two cab signal relays AP and BP, means operating when said reset relay and relay A are energized to energize relay AP or relay BP according as relay B is ener ized or deenergized, means for subsequently keeping relay AP or relay BP' energized as long as said reset relay is deenergized, and the brakes have not been applied automatically, means for givinga clear indication on a train when relays A and B are both energized, and means for giving a caution or a stop indication on the train according as relay BP is energized or both relays BP and AP are deenergized.

3. In combination, a stretch of railway track divided into blocks, an inert inductor located at the entrance to each block a trackway loop associated with each inductor, means for supplying each loop with alternating current of one character under clear conditions and of another character under caution conditions and for deenergizing the loop under stop conditions, intermittent inductive train-carried train controlling apparatus comprising the usual receiver coacting with said trackway inductorsand a normally deenergized' reset relay as well as an acknowledging switch, means operating when said acknowledging switch is reversed to energize said reset relay, two train-carried relays A and B, means including a receiver coacting, inductively with each trackway loop for energizingboth, relays if the loop is supplied FRANK H. NICHOLSON. 

